Automatic toilet bowl overflow prevention device

ABSTRACT

The automatic toilet bowl overflow prevention apparatus comprises of a water level sensor attaches to the rim of the toilet bowl, a hollow flexible tube connecting the water level sensor to an air vented toilet tank flapper. When the water level sensor trips, it opens an air valve and allows air to vent out from the air vented toilet tank flapper. Venting the air out of the air vented toilet tank flapper will close the toilet tank flush valve. Thus shutting off water to the toilet bowl and prevents it from overflowing. This apparatus uses an air vented toilet tank flapper for demonstration. An air vented toilet tank ball will work too. This invention is totally automatic and does not require any electrical power to operate.

SUMMARY OF INVENTION

[0001] This invention illustrates a simple apparatus to detect that water level in the toilet bowl has exceeded maximum safe level in the toilet bowl and shutoffs the water to the toilet bowl. Shutting off the water to the toilet bowl at this point prevents the toilet bowl from overflowing. There is no electrical power required to operate this apparatus.

[0002] The apparatus consists of a water level sensor attaches to the rim of the toilet bowl, a hollow flexible tube connecting the water level sensor to an air vented toilet tank flapper. In this invention, an air vented toilet tank flapper is used to demonstrate how the system works. The system will work with an air vented toilet tank ball too.

[0003] The water level sensor will open an air valve to allow air to flow out of the flexible tube attaching to the water level sensor coming from the air vented toilet tank flapper when it trips. The water level sensor will close the air valve when it is in the normal not tripped state to prevent air from leaving the flexible tube attaching to the water level sensor. The water level sensor uses a float to detect water level in the toilet bowl.

[0004] The air vented toilet tank flapper has an air chamber to maintain a positive buoyancy in order to keep the toilet tank valve open after it has been activated to the open position. The air chamber in the air vented toilet tank flapper has two opening. One opening is for the venting of the air and the other is for filling and draining of the water into and out of air chamber. The air chamber of the air vented toilet tank flapper is acting like a main ballast of a submarine. Opening the air vent and allowing water to flood the ballast will cause the air vented toilet tank flapper to become negative buoyancy and sink thus closing the toilet tank flush valve. Once the toilet tank flush valve is closed, the water in the air chamber of the air vented toilet tank flapper will drain by itself through gravity. The air chamber in the air vented toilet tank flapper is filled with air once the toilet tank flush valve is closed.

[0005] In normal usage, the water in the toilet bowl is below the trigger point of the water level sensor. In this state, the air vented toilet tank flapper operates like any conventional toilet tank flapper.

[0006] Now, the scenario of an overflow is about to occur. The user flushes the toilet bowl by pulling the toile tank flapper up to open the toilet tank flush valve. Once the toilet tank flush valve is forced open, it will remain open by the positive buoyancy state of the air vented toilet tank flapper. The water level sensor is in the none tripped state and the air vent passage to the air vented toilet tank flapper is closed. Upon detection of water level in the toilet bowl has passed the maximum allowable level in the toilet bowl, the water level sensor trips open and air is allow to vent out of the air vented toilet tank flapper. As water displaces the air inside the air vented toilet tank flapper, it becomes negative buoyancy and sink to close the toilet tank flush valve. Water flowing through the toilet tank flush valve is closed and a toilet bowl overflow is prevented.

[0007] The water level sensor is set where there is still room available inside the toilet bowl to accommodate the refill water coming from the toilet tank refill valve while the refill valve is refilling the toilet tank water.

[0008] This brief summary of the invention demonstrates how the apparatus shutoffs the water to the toilet bowl and prevents the toilet bowl from overflowing.

BRIEF DESCRIPTION OF DRAWINGS

[0009] The drawings refer below illustrate the prefer embodiment that is intended to illustrate and not to limit the invention.

[0010]FIG. 1 is the side view of a two pieces toilet. It shows the external view of the automatic toilet bowl overflow prevention device attached to the toilet at the preferred location.

[0011]FIG. 2 is the cut away front view of the toilet tank with the air vent tube and air vented toilet tank flapper.

[0012]FIG. 3 is the cut away front view of the toilet bowl with the water level sensor and air vent tube.

[0013]FIG. 4 is the air vented toilet tank flapper with the air vent tube.

[0014]FIG. 5 shows the air vented toilet tank ball with the air vent tube.

REFERENCE NUMERALS IN DRAWINGS

[0015]1 Air vent tube tank clip

[0016]2 Air vent tube

[0017]3 Water level sensor clip

[0018]4 Toilet bowl rim

[0019]5 Toilet bowl

[0020]6 Toilet tank

[0021]7 Toilet tank cap

[0022]8 Air vented toilet tank flapper

[0023]9 Toilet tank flush valve

[0024]10 Toilet tank overfill/refill tube

[0025]11 Toilet tank flapper chain

[0026]12 Clip

[0027]13 Toilet bowl water level sensor trip point

[0028]14 Toilet bowl normal water line.

[0029]15 Air vent tap

[0030]16 Air vented toilet tank ball

[0031]17 Water level sensor float

[0032]18 Water level sensor

[0033]19 Air chamber

[0034]20 Water port

DETAILED DESCRIPTION

[0035] With reference to FIG. 3, when the water level is at toilet bowl normal water line 14, the water level sensor 18 is in the normal off state. The air vent tube 2 of the air vented toilet tank flapper 8 in FIG. 2 is closed. In this state, the air vented toilet tank flapper 8 will operate like any conventional toilet tank flapper as shown in FIG. 4 with out air vent tap 15 and air vent tube 2.

[0036] Again, with reference to FIG. 3, when the water level is at toilet bowl water level sensor trip point 13, the water level sensor float 17 will be forced up and trips the water level sensor 18. In the tripped position, the water level sensor 18 open the air valve to allow air to escape the air vent tube 2. The air vent tube 2 is connected to the air vented toilet tank flapper 8 as shows in FIG. 2. With it's air vent tube 2 open, water enters and floods the air chamber 19 inside the air vented toilet tank flapper 8. Water displacing air in the air chamber 19 of the air vented toilet tank flapper 8 causes it to become negative buoyancy and sink. When the air vented toilet tank flapper 8 sinks, it closes the toilet tank flush valve 9. At this point, no more water flowing from the toilet tank flush valve 9 to the toilet tank bowl. Once the toilet tank flush valve 9 is closed, water in the air vented toilet tank flapper 8 will drain and any water that might enter the air vent tube 2 will be drained too.

[0037] A small amount of water will still flow into the toilet bowl 5 in FIG. 1 even after the toilet tank flush valve 9 in FIG. 2 is closed by the tripped water level sensor 18 in FIG. 1. This is the toilet bowl 5 refill water coming from the toilet tank refill valve. The toilet bowl 5 refill water will stop once the toilet tank refill valve shutoffs after the toilet tank refill valve finishes refilling the toilet tank.

[0038] The water level where the toilet bowl water level sensor trip point 13 in FIG. 3 will accommodate the water from the toilet tank refill valve. When the waste outlet of the toilet bowl 5 is not blocked, the water level in the toilet bowl 5 will never reach the toilet bowl water level sensor trip point 13.

[0039] The water level sensor clip 3 in FIG. 3 allows the water level sensor 18 to be moved up or down to set the toilet bowl water level sensor trip point 13 in the toilet bowl 5. It is preferred that water level sensor be mounted away from the toilet tank and close to the front of the toilet bowl. The water level sensor can be made of none metallic material to prevent rusting and reduce cost.

[0040] The water level sensor 18 in FIG. 3 is a water level float valve. However, It can be a float switch also. But using the float switch requires electrical power to control a said solenoid valve to control the opening and closing of the air vent tube 2. The preferred embodiment is a water level float valve. The pressure inside the air vent tube 2 is at its peak when the air vented toilet tank flapper 8 in FIG. 2 is first opened. For a {fraction (3/16)} inch inside diameter air vent tube 2, the pressure that the water level float 17 need to over come to open is around 1.6 ounce.

[0041] The air vent tube tank clip 1 in FIG. 1 helps protect the air vent tube 2 from being crushed by the toilet tank cap 7. The air vent tube clip 1 should be made of non metallic material strong enough to prevent the air vent tube 2 from being crushed by the toilet tank cap 7 and any light ornaments that the user put on the toilet tank cap 7.

[0042] The routing of the air vent tube 2 in FIG. 2 should prevent the air vent tube 2 from interference of other parts inside the toilet tank. Not all of the toilet tank parts like refill valve apparatus or toilet tank flush level are shown in FIG. 2. The reason is to keep the drawing simple to demonstrate the working of the automatic toilet bowl overflow prevention device. The clip 12 can be used in routing the air vent tube 2. There should be no kink in the air vent tube 2. The air vent tube 2 can be made of flexible, soft and strong material like silicon tubing. Rubber tubing like surgical tubing can also be use.

[0043]FIG. 4 and FIG. 5 show the preferred location of the air vent tap 15. This is the preferred location because when the air vented toilet tank flapper valve 9 is opened, the air space inside the air chamber 19 has its highest air ceiling around this location. The air vent tap 15 should always be at the top of the air ceiling inside the air chamber 19. The preferred size of the air vent tap 15 is {fraction (3/16)} inches inside diameter. 

We claim:
 1. An automatic toilet bowl overflow prevention device comprising: a water level float valve comprising a float, an air inlet and an air outlet; a flexible tube comprising an air inlet port and an air outlet port, said air inlet port of said water level float valve being connected to said air outlet of said flexible tube; an air vented toilet tank flapper comprising an air chamber, an air vent port, and a water port, said air inlet port of said flexible tube being connected to said air vent port of said air vented toilet tank flapper. 